# vvatan2f(_:_:_:_:) Calculates the arctangent of each pair of elements in two arrays of single-precision values. ``` func vvatan2f(_: UnsafeMutablePointer, _: UnsafePointer, _: UnsafePointer, _: UnsafePointer) ``` ## Discussion ### Parameters: - parameter 1: The output array, *z*. - parameter 2: The input array, *y*. - parameter 3: The input array, *x*. - parameter 4: The number of elements in the arrays. The signs of both arguments are used to determine the quadrant of the calculated value. The following special values of `x` and `y` produce the given value of `z`: |y |x |z (result)| |--------|------|----------| |`+/-0` |`-0` |`+/-pi` | |`+/-0` |`+0` |`+/-0` | |`+/-0` |`<0` |`+/-pi` | |`+/-0` |`>0` |`+/-0` | |`>0` |`+/-0`|`+pi/2` | |`<0` |`+/-0`|`-pi/2` | |`+/-y` |`-inf`|`+/-pi` | |`+/-y` |`+inf`|`+/-0` | |`+/-inf`|`x` |`+/-pi/2` | |`+/-inf`|`-inf`|`+/-3pi/4`| |`+/-inf`|`+inf`|`+/-pi/4` | --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)